Hybrid optical fiber MEMS scanner

Abstract

An optical scanner includes a cantilevered optical member protruding from the base portion and a transducer assembly comprising one or more piezoelectric actuators coupled to the cantilevered optical member and configured to induce motion of the cantilevered optical member in a scan pattern. In some cases, the cantilevered optical member has a tapered shape with a distal end narrower than a proximal end adjacent to the base portion of the optical scanner. In some cases, the cantilevered optical member has an elongated width along a first plane and includes a plurality of waveguides. The transducer assembly is configured to induce motion of the cantilevered optical member in a second plane orthogonal to the first plane.

What is claimed is: 
     
       1. An optical scanner, comprising:
 a cantilevered optical member; 
 a base portion, the base portion comprising:
 an upper transducer assembly, wherein the upper transducer assembly includes an upper channel for accommodating the cantilevered optical member; and 
 a lower transducer assembly, wherein the lower transducer assembly includes a lower channel for accommodating the cantilevered optical member; wherein the cantilevered optical member protrudes from the base portion; and 
 
 a first pair of piezoelectric actuators coupled to the upper transducer assembly and a second pair of piezoelectric actuators coupled to the lower transducer assembly and configured to induce motion of the cantilevered optical member in a scan pattern. 
 
     
     
       2. The optical scanner as recited in  claim 1 , wherein the cantilevered optical member has a tapered shape with a distal end narrower than a proximal end adjacent to the base portion of the optical scanner. 
     
     
       3. The optical scanner of  claim 1 , wherein the cantilevered optical member comprises an optical fiber. 
     
     
       4. The optical scanner of  claim 1 , wherein the cantilevered optical member includes one or more enlarged diameter portions and wherein the upper channel and the lower channel are sized to accommodate the enlarged diameter portions. 
     
     
       5. The optical scanner of  claim 1 , wherein the upper channel comprises a multi-section upper channel with a plurality of upper channel segments spaced apart from one another by one or more upper openings defined by the upper transducer assembly or wherein the lower channel comprises a multi-section lower channel with a plurality of lower channel segments spaced apart from one another by one or more lower openings defined by the lower transducer assembly. 
     
     
       6. The optical scanner of  claim 1 , wherein the cantilevered optical member includes one or more metallized portions. 
     
     
       7. The optical scanner of  claim 1 , wherein the upper transducer assembly includes one or more capacitive sensing regions configured to monitor motion of the cantilevered optical member during motion or wherein the lower transducer assembly includes one or more capacitive sensing regions configured to monitor motion of the cantilevered optical member during motion. 
     
     
       8. The optical scanner of  claim 7 , further comprising an external circuit coupled to the one or more capacitive sensing regions. 
     
     
       9. The optical scanner of  claim 7 , wherein the upper transducer assembly includes two upper capacitive sensing regions or wherein the lower transducer assembly includes two lower capacitive sensing regions configured to monitor motion of the cantilevered optical member during motion. 
     
     
       10. The optical scanner of  claim 9 , wherein the upper transducer assembly includes an upper H-shaped opening positioned to electrically isolate the two upper capacitive sensing regions from one another or wherein the lower transducer assembly includes a lower H-shaped opening positioned to electrically isolate the two lower capacitive sensing regions from one another. 
     
     
       11. The optical scanner of  claim 1 , wherein the upper transducer assembly includes an upper hub portion, an upper opening, and one or more upper flexures, wherein the upper hub portion is positioned within the upper opening and suspended within the upper opening by the one or more upper flexures, or wherein the lower transducer assembly includes a lower hub portion, a lower opening, and one or more lower flexures, wherein the lower hub portion is positioned within the lower opening and suspended within the lower opening by the one or more lower flexures. 
     
     
       12. The optical scanner of  claim 11 , wherein each of the first pair of piezoelectric actuators have an end coupled to the upper hub portion or wherein each of the second pair of piezoelectric actuators have an end coupled to the lower hub portion. 
     
     
       13. The optical scanner of  claim 1 , wherein the upper transducer assembly and the lower transducer assembly comprises one or more glass frits positioned for bonding the upper transducer assembly and the lower transducer assembly to one another. 
     
     
       14. The optical scanner of  claim 1 , further comprising an adhesive positioned between the upper transducer assembly and the lower transducer assembly for bonding the upper transducer assembly and the lower transducer assembly to one another. 
     
     
       15. The optical scanner of  claim 1 , wherein the upper transducer assembly or the lower transducer assembly comprises one or more openings sized and shaped for accommodating a kinematic alignment features. 
     
     
       16. The optical scanner of  claim 1 , wherein the upper transducer assembly comprises a layer of monocrystalline silicon or wherein the lower transducer assembly comprises a layer of monocrystalline silicon. 
     
     
       17. The optical scanner of  claim 1 , wherein the cantilevered optical member comprises a silicon beam including one or more optical waveguides. 
     
     
       18. The optical scanner of  claim 1 , wherein the upper transducer assembly includes an upper pair of tapered protrusions positioned to support anchoring of the first pair of piezoelectric actuators or wherein the lower transducer assembly includes a lower pair of tapered protrusions positioned to support anchoring of the second pair of piezoelectric actuators. 
     
     
       19. The optical scanner of  claim 1 , further comprising a drive circuit coupled to the first pair of piezoelectric actuators and the second pair of piezoelectric actuators. 
     
     
       20. The optical scanner of  claim 1 , further comprising a light source optically coupled to the cantilevered optical member to direct light along the cantilevered optical member.